The present invention relates to a methodology for assessing the likelihood that a fetus will be at enhanced risk to develop fetal heart disease. The methodology utilizes maternal testing for an antecedent streptococcal infection. The invention also encompasses a method for preventing the formation of such heart disease.
Hypoplastic left heart syndrome (HLHS) and its variants (including aortic stenosis and mitral stenosis) are severe congenital heart defects with substantial associated morbidity and mortality. The primary disease process involves damage and underdevelopment of the left-side heart structures such that the end result is an abnormal heart not capable of supporting the normal circulation of a newborn. Treatment currently entails either high risk and costly multistage reconstructive surgery or heart transplantation, all commencing immediately after birth. These left-side heart structure defects, as well as similar right-side heart structure defects, are collectively referred to herein as “fetal heart disease.”
The etiology of this and associated conditions is not currently known. A genetic etiology has been proposed based on limited familial occurrence, but no genetic mutation has been attributed to this disease or its variants. Indeed, HLHS and associated conditions have been linked to nearly every single chromosomal and syndromic anomaly. Although less common, congenital heart defects affecting the right-side of the heart result in similar underdevelopments of the right-side heart structures (such as pulmonary stenosis or pulmonary atresia or tricuspid valve stenosis). This can also result in disabling heart disease of the newborn and, similar to the previously discussed defects, their etiology remains unknown. It would be a very positive development to understand the etiology of fetal heart disease so that a given fetus's predisposition to such condition could be evaluated and, if the predisposition is high, appropriate palliative measures can be taken, perhaps while the fetus is still in utero.